The field of the present invention is apparatus and methods for draining fluid from a body cavity of a patient.
Drainage tubes are typically used in many types of thoracic surgeries, especicially following cardiac surgery, and to treat cardiac or pulmonary conditions such as pneumothorax or pneumonia. Thoracic surgery may be performed on a patient for a variety of reasons, such as to remove a portion of a patient""s lung, repair a patient""s heart or the vessels of the lungs and heart, to operate on the esophagus, to determine whether a patient has lung or chest disease, or following injury to the lungs or the pleura, which is a membrane that covers the lungs. Such drainage tubes are distinct in medical usage from catheters inserted into passageways in the body, particularly as to size.
A drainage tube may be inserted through the skin and into the thoracic cavity of a patient. Typically, a tube is inserted through an intercostal space, which is the space between adjacent ribs. Once intubated in the patient, a tube may be used to drain fluids, including both gases such as air and liquids such as blood serum or pus, from the patient""s thoracic cavity. Drainage may be carried out by suction with liquids and gases draining through the center lumen of the tube.
One specific application for drainage tubes is the treatment of conditions that can cause a patient""s lung to collapse. Between the lungs and the membrane lining the chest wall is the pleural space. The pleural space facilitates breathing by having a vacuum created within the space as the volume increases with diaphragm and rib movement and forcing the lungs to expand. When the pleural space has been violated or cut into, such as during chest surgery, air rushes in and deflates or collapses the lungs. Air or other gases, as well as blood and other body fluids may enter the pleural space, destroying the ability of the space to make or maintain a vacuum normally maintained in the pleural space, and potentially causing the lung to collapse. To return the lung to normal size and function, air and fluids may be removed from the pleural space using a tube.
During or after surgery, in addition to using a tube to drain fluids (including liquids, air and other gases) from the patient""s chest cavity, it may be desirable to reduce the patient""s body temperature below normal body temperature so that the patient experiences hypothermia. Many advantages of hypothermia are known. By way of example, it has been found desirable to lower the temperature of body tissue in order to reduce the metabolism of the body. This has been particularly desirable in surgical applications where the reduced metabolism has made it possible to more easily accommodate lengthy operative procedures. In cases of stroke and several other pathological conditions, hypothermia also reduces the permeability of the blood/brain barrier. It inhibits release of damaging neurotransmitters and also inhibits calcium-mediated effects. Hypothermia also inhibits brain edema and lowers intracranial pressure. In other cases, it may be desireable to reduce the body temperature of a patient having a fever to a normal body temperature.
In yet other situations, it may be desirable to raise the patient""s body temperature. Control of a patient""s temperature may be problematic during hospital stays and particularly during active interventions such as thoracic surgery. The patient""s body temperature may drift too low during surgery, potentially being deterimental to the patient""s health. Body temperature often must be artificially maintained during surgery and post-operatively.
Conventional therapies used to manage patient temperature include acetaminophen (Tylenol), cooling blankets, heating blankets such as warm water blankets, forced warm or cool air, heat lamps, endovascular catheters, ice packs, ice baths, cold or warm infusions, ambient room cooling or warming, and cold saline rectal or gastric lavages. For some of the conventional therapies, the warming or cooling rates are restricted by the body""s ability to resist surface cooling or heating with vasodilation and sweating. The conventional approaches to cooling a patient also may require additional steps, may require excessive time and do not provide for precise control of patient temperature over long periods of time. Further, some of these devices cover a significant portion of a patient""s body, inhibiting access to the patient.
Other techniques for controlling patient temperature employ intravascular catheters that may be inserted into the patient""s venous system. A fluid may be circulated through such catheters in a closed loop and exchange heat with blood flowing in the venous system, and may improve the patient""s medical outcome. Such techniques may require that an additional incision be made so that the catheter may be advanced into the patient""s venous system.
The present invention is directed to a drainage tube with a heat exchange function and methods for its use. A heat exchange element or elements is combined with a drainage lumen and one or more drainage ports to provide efficient temperature control of, drainage of and access to tissue in the patient""s thoracic or other body cavity.
In a first separate aspect of the invention, a drainage tube comprises a heat exchange element that exchanges heat with tissue in the patient""s thoracic or other body cavity, and a drainage lumen that communicates with tissue in the patient""s thoracic or other body cavity through one or more drainage ports.
In a second separate aspect of the invention, a drainage tube comprises a heat exchange element that includes a balloon that extends distally from the distal end of the elongate body when operatively disposed.
In a third separate aspect of the invention, a drainage tube comprises a heat exchange element that includes an everting balloon that is at least partially contained in the elongate body during intubation of the drainage tube, the everting balloon extending distally from the distal end of the drainage tube when operatively disposed and inflated with heat exchange fluid.
In a fourth separate aspect of the invention, a drainage tube comprises a generally tubular elongate body defining an inflow lumen, an outflow lumen, and at least one drainage lumen. The inflow and outflow lumens circulate heat exchange fluid within one or more heat exchange elements connected with a distal, implantable portion of the drainage tube, while the drainage lumen provides a drainage channel for fluids (including gases) in the patient""s thoracic or other body cavity.
In a fifth separate aspect of the invention, a drainage tube is provided with a drainage lumen that communicates with drainage ports that are disposed along the drainage tube at spaced intervals, such that the drainage tube may simultaneously drain fluids from different locations in the patient""s thoracic or other body cavity, so as to increase the drainage rate and promote evenly distributed drainage.
In a sixth separate aspect of the invention, a drainage tube having a heat exchange function is provided with one or more infusion lumens, each infusion lumen having one or more infusion ports, the infusion ports being disposed along the drainage tube at spaced intervals, such that the drainage tube may be used to simultaneously introduce various infusion fluids into the patient at different locations in the patient""s thoracic or other body cavity, so as to target different areas of the thoracic cavity or so as to more evenly distribute an infusion fluid throughout the thoracic or other body cavity.
In a seventh separate aspect of the invention, a heat exchange drainage tube is provided with multiple heat exchange balloons that are spaced along the distal portion of the elongate body to provide controlled and balanced heat transfer, with a gap between balloons to provide the drainage tube with flexibility.
In an eighth separate aspect of the invention, a heat exchange drainage tube is provided with multiple balloons have a gap between balloons, so that at least one drainage port may be disposed in the gap.
In a ninth separate aspect of the invention, a drainage tube comprises one or more heat exchange elements, a heating element, and a generally tubular elongate body defining a flow lumen and a drainage lumen. The flow lumen transports heat exchange fluid between one or more heat exchange elements connected with a distal, implantable portion of the drainage tube. The heating element is disposed on or in the distal portion of the drainage tube. The drainage lumen provides a drainage channel for fluids from the patient""s thoracic or other body cavity.
In a tenth separate aspect of the present invention, it is contemplated that combinations of the foregoing separate aspects may be incorporated into a single embodiment.
Therefore, it is an object of the present invention to provide a drainage tube with a heat exchange function and methods for its use. Other and further objects and advantages will appear hereafter.